Hi Peter, the immediate thought is DSL ( or ADSL) or even ISDN lines. I
would not lay too much store by BT "engineers" not being able to find it.
These guys have little or no RF experience in general. Because it is so
wirespread, I would suggest it is a system effect rather than a fault
somewhere, and it would seem to correlate with the increased penetration of
"broadband". This could explain why some "diss poles" are not as noisy as
others.
I do still have a collegue who is an amateur who worked in the EMC group at
Martlesham for many years (now retired), after starting as an RI officer in
N.London. He still has contacts and I believe does consultative work. I
would be happy to send him the imformation /tape if you think it would help.
Cheers de Alan G3NYK
[email protected]
----- Original Message -----
From: "g3ldo" <[email protected]>
To: <[email protected]>
Sent: 09 June 2004 09:27
Subject: LF: Re: Off Topic---QRM
For many months now I have been experiencing a peculiar electrical
interference. It is a rasping sound rather like a spark transmitter and
sending something like NX in very bad morse at around 5WPM. The QRM is
broadband centred around 14MHz and is on 24hrs a day.
I have reported the matter to BT who hav been out to investigate but are
unable to find the source or even say what it is.
I have also sent a tape to David Lauder, the RSGB EMC guru but even he
does
not know what it is.
With my bicycle mobile I have travelled around the vicinity in a radius of
around 3km of my QTH and find the QRM widespread with hot spots often by
telephone line distribution poles. Most telephone poles do not carry the
interference.
The interference does not affect 136kHz - hence Off Topic.
Regards,
Peter, G3LDO
e-mail <[email protected]>
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